Positional Neutralization - Linguistics - University of California ...

maximum of 556 Hz., close to the mean for this speaker - see section 3.6.1. above and the
experimental results in Chapter 2). The pretonic vowel, however, does sound
impressionistically at least more 'a'-like than the final. An important reason for this could
be that, in addition to the fact that the amplitude of the pretonic and stressed vowels is
substantially higher than that of the final vowel throughout, the amplitude of the first
pretonic vowel is more or less equally high throughout its duration, including, obviously
at its center where the F1 maximum occurs.
For the final vowel, however, this is not the case. The amplitude of the final
vowel decreases steadily throughout, becoming extremely low and ultimately fading to
nothing by the end. What is more, the peak F1 for the final vowel occurs relatively far
into its course, approximately 90 ms into the vowel. By this point, of course, the
amplitude of the vowel has fallen considerably, and only gets lower. With the application
of final lengthening, the vowel has become extremely long by comparison, and assuming
that gestural stiffness is lowered (meaning slowing), but target displacement is not
reduced, this means that the time to peak displacement will have increased significantly.
What seems to be occurring, in other words, is that the "sonority enhancement" discussed
by Cho (2001) is taking place, but the higher F1 peak it produces is coming quite late
relative to the gradually decaying amplitude of the vowel. This has the effect of making
the part of the vowel with the highest F1 cooccur with the part in which perceptibility is
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